Your brother gives you a "frequent flyer" coupon, which allows you to pay $200 less than the regular airfare on any flight you choose to take. The coupon can be used any time, and you often fly. The cost of Toronto/Vancouver airfare is $500 for a regular ticket. You value the trip from Toronto to Vancouver at $400. Should you use the coupon, pay $300 and fly to Vancouver? Explain your answer.